mjit_compile.c: resurrect local variable stack

This optimization was reverted on r63863, but this commit resurrects the
optimization to skip some sp motions on JIT execution.

tool/ruby_vm/views/_mjit_compile_insn_body.erb: ditto
tool/ruby_vm/views/_mjit_compile_insn.erb: ditto

insns.def: resurrect handles_frame as handles_stack, which was deleted
on r63763.
tool/ruby_vm/models/bare_instructions.rb: ditto

vm_insnhelper.c: prevent moving sp outside insns.def to allow modifying
it by JIT.

* Optcarrot benchmark

$ benchmark-driver benchmark.yml --rbenv 'before --jit;after --jit' --repeat-count 12 -v
before --jit: ruby 2.6.0dev (2018-07-17 trunk 63987) +JIT [x86_64-linux]
after --jit: ruby 2.6.0dev (2018-07-17 local-stack 63987) +JIT [x86_64-linux]
last_commit=mjit_compile.c: resurrect local variable stack
Calculating -------------------------------------
                         before --jit  after --jit
Optcarrot Lan_Master.nes       70.518       72.144 fps

Comparison:
             Optcarrot Lan_Master.nes
             after --jit:        72.1 fps
            before --jit:        70.5 fps - 1.02x  slower

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63988 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 5 insertions, 0 deletions

diff --git a/tool/ruby_vm/models/bare_instructions.rb b/tool/ruby_vm/models/bare_instructions.rb
index 297a93f5b2..f540295531 100755
--- a/tool/ruby_vm/models/bare_instructions.rb
+++ b/tool/ruby_vm/models/bare_instructions.rb
@@ -101,6 +101,10 @@ class RubyVM::BareInstructions
     }.join
   end
 
+  def handles_stack?
+    /\b(false|0)\b/ !~ @attrs['handles_stack'].expr.expr
+  end
+
   def inspect
     sprintf "#<%s %s@%s:%d>", self.class.name, @name, @loc[0], @loc[1]
   end
@@ -125,6 +129,7 @@ class RubyVM::BareInstructions
     generate_attribute 'rb_num_t', 'retn', rets.size
     generate_attribute 'rb_num_t', 'width', width
     generate_attribute 'rb_snum_t', 'sp_inc', rets.size - pops.size
+    generate_attribute 'bool', 'handles_stack', false
   end
 
   def typesplit a